1. Field of the Invention
The present invention relates to a game apparatus and a game program. More specifically, the present invention relates to a game apparatus and a game program capable of playing a game in response to a player adding a motion to a controller itself.
2. Description of the Related Art
One example of a game apparatus of such a kind is disclosed in a nonpatent literature 1 (http://www.nintendo.co.jp/wii/controllers/index.html). In the related, art, “Wii remote controller” (Wii: registered trademark) has a three-axis acceleration sensor for detecting changes of tilts and motions of itself. “Nunchaku” also has a three-axis acceleration sensor.
In order to perform the game on the outputs from the three-axis acceleration sensors, the player perform an operation by swinging and tilting the Wii remote controller and the Nunchaku while holding the Wii remote controller with one hand and the Nunchaku the other hand.
In the aforementioned nonpatent literature 1, since the acceleration sensor is used, the change of the attitude of the controller can be determined by the gravitational acceleration, but there is a problem of being unable to detect the rotation about a yaw direction, that is, in the direction of the gravitational force. Furthermore, if acceleration other than gravity is highly applied, there is a problem of being unable to accurately calculate the orientation. Furthermore, there is a problem that in a case that a quick rotating operation, not a slow change of the orientation, is performed, complex processing is required in order to determine an addition of acceleration.